import 'dart:io';

import 'package:drift/drift.dart';
import 'package:drift/native.dart';
import 'package:flutter/services.dart' show rootBundle;
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';
import 'package:sqlite3/sqlite3.dart';
import 'package:sqlite3_flutter_libs/sqlite3_flutter_libs.dart';

QueryExecutor openConnection() {
  return LazyDatabase(() async {
    // put the database file, called db.sqlite here, into the documents folder
    // for your app.
    final dbFolder = await getApplicationDocumentsDirectory();
    final file = File(p.join(dbFolder.path, 'app.db'));

    if (!await file.exists()) {
      // Extract the pre-populated database file from assets
      final blob = await rootBundle.load('assets/my_database.db');
      final buffer = blob.buffer;
      await file.writeAsBytes(
        buffer.asUint8List(blob.offsetInBytes, blob.lengthInBytes),
      );
    }

    // Also work around limitations on old Android versions
    if (Platform.isAndroid) {
      await applyWorkaroundToOpenSqlite3OnOldAndroidVersions();
    }

    // Make sqlite3 pick a more suitable location for temporary files - the
    // one from the system may be inaccessible due to sandboxing.
    final cachebase = (await getTemporaryDirectory()).path;
    // We can't access /tmp on Android, which sqlite3 would try by default.
    // Explicitly tell it about the correct temporary directory.
    sqlite3.tempDirectory = cachebase;

    return NativeDatabase.createInBackground(file);
  });
}
